In an experiment, the length of an object is measured to be 6.50 cm. This measured value can be written as 0.0650 m.The number of significant figures on 0.0650m is
- 3
- 4
- 2
- 5
The Correct Option is A
Solution and Explanation
The correct answer is option (A): 3
Significant figures refer to the digits that carry meaning contributing to the precision of a number. The rules to determine significant figures are:
- All non-zero digits are significant.
- Zeros between non-zero digits are significant.
- Leading zeros (zeros before the first non-zero digit) are not significant.
- Trailing zeros (zeros after a decimal and a non-zero digit) are significant.
- In scientific (exponential) notation, only the number before the exponent counts for significant figures.
Given number: \( 0.0650 \)
- Leading zeros "0.0" are not significant.
- Digits "6", "5", and the trailing zero "0" (after decimal) are significant.
So, the number of significant figures = 3
Answer: Option (A) — 3 significant figures
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Concepts Used:
Units and Measurement
Unit:
A unit of a physical quantity is an arbitrarily chosen standard that is broadly acknowledged by the society and in terms of which other quantities of similar nature may be measured.
Measurement:
The process of measurement is basically a comparison process. To measure a physical quantity, we have to find out how many times a standard amount of that physical quantity is present in the quantity being measured. The number thus obtained is known as the magnitude and the standard chosen is called the unit of the physical quantity.
Read More: Fundamental and Derived Units of Measurement
System of Units:
- CGS system
- FPS system
- MKS system
- SI units
Types of Units:
Fundamental Units -
The units defined for the fundamental quantities are called fundamental units.
Derived Units -
The units of all other physical quantities which are derived from the fundamental units are called the derived units.